U.S. patent number 4,484,419 [Application Number 06/309,253] was granted by the patent office on 1984-11-27 for block for wet abrading.
This patent grant is currently assigned to Minnesota Mining and Manufacturing Company. Invention is credited to Conrad T. Freerks.
United States Patent |
4,484,419 |
Freerks |
November 27, 1984 |
Block for wet abrading
Abstract
An abrading block (10) especially suited for wet hand surface
finishing operations is provided. The abrading block (10) comprises
a body (11) having a bottom surface (12) having an opening (13)
therein. Bottom surface (12) is adapted to hold a sheet of abrasive
material (14), also having an opening (15) therethrough, in a
substantially planar position with an abrasive working face (16)
exposed and with the opening (15) through the sheet of abrasive
material (14) aligned with the opening (13) in the bottom surface
(12). The body (11) also includes an opposite surface (17) capable
of being grasped by the hand of the user, a cavity (18) capable of
containing liquid, and a conduit (19) extending from the opening
(13) in the bottom surface (12) to the cavity (18) for passage of
liquid from the cavity (18) to the opening (13). An air vent (20)
may be provided through the body (11 ) into the cavity (18) to
permit liquid to flow therefrom under gravity. The abrading block
(10) also includes a porous member (21) having a first portion (22)
fitted into the conduit (19) to substantially prevent the free flow
of liquid from the cavity (18) and an exposed wiping end portion
(23) extending from the opening (13) to or beyond the abrasive
working face (16). The porous member (21) is formed of a material
which will permit the controlled passage of liquid as its exposed
wiping end portion (23) is brought into contact with and passed
over the surface (24) being finished during an abrading operation
in a sufficient quantity to wet at least a portion of the surface
(24) with liquid. Opposite surface (17) may include a handle
(25).
Inventors: |
Freerks; Conrad T. (Maplewood,
MN) |
Assignee: |
Minnesota Mining and Manufacturing
Company (Saint Paul, MN)
|
Family
ID: |
23197399 |
Appl.
No.: |
06/309,253 |
Filed: |
October 7, 1981 |
Current U.S.
Class: |
451/523;
451/450 |
Current CPC
Class: |
B24D
15/04 (20130101) |
Current International
Class: |
B24D
15/04 (20060101); B24D 15/00 (20060101); B24D
015/00 () |
Field of
Search: |
;51/358,213,391,392,393,267 ;401/198,199,207 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
8280 |
|
1903 |
|
GB |
|
2075384 |
|
Nov 1981 |
|
GB |
|
Primary Examiner: Schmidt; Frederick R.
Assistant Examiner: Schad; Steven P.
Attorney, Agent or Firm: Sell; Donald M. Smith; James A.
Francis; Richard
Claims
I claim:
1. An abrading block especially suited for manual abrading
operations, said abrading block comprising
(1) a body comprising:
(a) a bottom surface having an opening therein and being adapted to
hold a sheet of abrasive material, having an opening therethrough,
in a substantially planar position with an abrasive working face
exposed and with the opening through said sheet of abrasive
material aligned with the opening in said bottom surface;
(b) an opposite surface capable of being grasped by the hand of the
user;
(c) a cavity capable of containing liquid; and
(d) a conduit extending from said opening in said bottom surface to
said cavity for passage of liquid from said cavity to said opening
in said bottom surface; and
(2) a porous member fitted into said conduit to substantially
prevent the free flow of liquid from said cavity having an exposed
wiping end extending from said opening to or beyond said abrasive
working face, said porous member being formed of a material which
will permit the controlled passage of liquid as said exposed end is
brought into contact with and passed over a surface being finished
during an abrading operation in sufficient quantity to wet at least
a portion of said surface being finished with liquid.
2. The abrading block of claim 1 wherein said body is formed of a
semi-rigid but flexible material.
3. The abrading block of claim 1 wherein said porous member is a
sponge.
4. The abrading block of claim 1 wherein said sheet of abrasive
material is a coated abrasive sheet having pressure-sensitive
adhesive on a surface opposite said abrasive working face to
facilitate attachment thereof to said bottom surface and said
bottom surface includes means for facilitating attachment of the
pressure-sensitive adhesive surface of said coated abrasive
sheet.
5. The abrading block of claim 1 wherein said body includes an air
vent from said opposite surface into said cavity to permit liquid
to flow.
Description
TECHNICAL FIELD
This invention relates to a manually operated abrading tool having
a means of dispensing liquid onto a surface being finished during
an abrading operation.
BACKGROUND ART
Manually operated abrading tools sometimes called abrading or
sanding blocks have been utilized for a considerable period of time
to prepare various surfaces, e.g., prior to application of paint.
Such abrading blocks typically consist of a body adapted to hold a
sheet of abrasive material with its exposed abrasive working face
in a planar configuration. Such abrading blocks are commonly used
for preparation of motor vehicle bodies for refinishing.
Most abrading blocks are of the dry type. For certain applications,
however, it is highly desirable to lubricate the surface being
finished by means of liquid such as water so that the abrasive
working face will not become filled or clogged. Water has been
applied by first wetting the surface being finished or by dipping
the abrading block containing the abrasive sheet into water prior
to use. Such methods provide only limited quantities of water.
Other devices have been employed to provide a more continuous
supply of water to the surface being finished. For example, Brown
(U.S. Pat. No. 2,904,940) discloses a wedge-shaped sander including
a body which has openings over which a coated abrasive web is
attached. As the tool is used, water is discharged through
interstices in the abrasive web. Such a device, however, cannot be
employed with conventional coated abrasive sheet materials because
they are generally impervious. Additionally, there is little or no
control of the flow of water from Brown's device because the water
will continuously flow through the openings and the porous backing
of the abrasive material.
Additionally, Carroll et al (U.S. Pat. No. 2,954,649) discloses a
cleaning pad and holder therefor which utilizes an abrasive grid
cloth held with a frame onto the surface of a sponge. Like Brown,
Carroll et al require a porous abrasive sheet and have little
control over the flow of the liquid from the sponge to the surface
of the workpiece because there is no direct contact of the sponge
with the surface being finished.
DISCLOSURE OF INVENTION
The present invention provides an abrading block which includes a
means of controllably dispensing liquid onto the surface being
finished during the abrading operation. The abrading block of the
present invention utilizes conventional coated abrasive sheet
materials, not requiring a coated abrasive sheet material having a
porous backing material.
The abrading block of the invention comprises a body which has a
bottom surface having an opening therein. The body is adapted to
hold on the bottom surface a sheet of abrasive material having an
opening therethrough, in a substantially planar position with an
abrasive working face exposed. The opening through the sheet of
abrasive material is aligned with the opening in the bottom
surface. Of course, the sheet of abrasive material may have more
than one opening, provided a sufficient number of such openings are
aligned with the opening in the bottom surface of the body to
permit adequate passage of liquid. An opposite surface of the body
is capable of being grasped by the hand of the user. The body also
contains a cavity capable of containing liquid. A conduit extends
from the opening in the bottom surface to the cavity for passage of
liquid from the cavity to the opening in the bottom surface. The
body may include an air vent into the cavity to permit liquid to
flow therefrom under gravity. A porous member is fitted into the
conduit to substantially prevent the free flow of liquid from the
cavity. The porous member has an exposed wiping end extending from
the opening to or beyond the abrasive working face. The porous
member is formed of a material which will permit the controlled
passage of liquid as the exposed end is brought into contact with
and passed over the surface being finished during an abrading
operation in sufficient quantities to wet at least a portion of the
surface with liquid.
In the preferred embodiment, the body is formed of a semi-rigid but
flexible material and the porous member is a hydrophilic sponge.
Because of the popularity of coated abrasive sheet materials having
pressure-sensitive adhesive on the backside to facilitate
attachment, the bottom surface of the body preferably includes
means for facilitating attachment of the pressure-sensitive
adhesive of such coated abrasive sheet materials.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of the abrading block of the present
invention with a sheet of abrasive material mounted thereon, the
sheet being partly cut away to show detail of the block.
FIG. 2 is a cross sectional view of the abrading block in FIG. 1
(taken at line 2--2) in contact with a surface to be abraded.
FIG. 3 is a plan view of the bottom surface of the abrading block
depicted in FIG. 1.
BEST MODE FOR CARRYING OUT THE INVENTION
Referring now to FIGS. 1-3, the abrading block 10 of the present
invention comprises a shaped body 11 having a bottom surface 12
having an opening 13 therein. Bottom surface 12 is adapted to hold
a sheet of abrasive material 14, also having an opening 15
therethrough, in a substantially planar position with an abrasive
working face 16 exposed. Opening 15 of the sheet of abrasive
material 14 is aligned with opening 13 in the bottom surface 12.
Body 11 also includes an opposite surface 17 capable of being
grasped by the hand of the user, a cavity 18 capable of containing
liquid, and a conduit 19 extending from opening 13 in bottom
surface 12 to cavity 18 for passage of liquid from cavity 18
through opening 13. An air vent 20 may be provided through body 11
into cavity 18 to permit liquid to flow therefrom under gravity and
to permit easy filling of cavity 18 by submersion of abrading block
10 in liquid. A liquid supply line may be connected to vent 20 to
provide a continuous liquid supply for use situations permitting
this modification.
Abrading block 10 also includes a porous member 21 having a first
portion 22 fitted into conduit 19 to substantially prevent the free
flow of liquid from cavity 18 and an exposed wiping end portion 23
extending from opening 13 to abrasive working face 16. Porous
member 21 is formed of a material which will permit the controlled
passage of liquid as its exposed end 23 is brought into contact
with and passed over surface 24 being finished during an abrading
operation in a sufficient quantity to wet at least a portion of
surface 24 with liquid. Body 11 is formed of any material which is
sufficiently rigid to sustain the forces encountered in
conventional abrading operations and prevent undue compression of
porous element 21 or constriction of cavity 18 to cause the
premature expulsion of liquid therefrom. Body 11, for example, may
be made of wood, rigid plastic material, metal and the like. The
preferred material for forming body 11 is a rigid but flexible
polyurethane foam. Opposite surface 17 of body 11 may be shaped to
provide a configuration, such as handle 25, which is more adapted
for grasping.
The preferred shape of bottom surface 12 is an annular shape,
having a central opening into which porous member 21 is fitted, for
use with a correspondingly-shaped annular coated abrasive sheet.
Other shapes are also contemplated, of course.
Opening 13 in bottom surface 12 may be round, as shown, or any
other convenient shape such as square, triangular, oval, etc.
Porous member 21 is preferably formed of a hydrophilic sponge
material which, when inserted into conduit 19, will substantially
prevent the free flow of liquid but permits the passage of liquid
therethrough as exposed end 23 is wiped against surface 24. Other
suitable materials for formation of porous element 21 include wads
of cotton batting or other fibrous materials.
Cavity 18 may be any convenient shape and may even be extremely
large as compared to the size of porous member 21 or porous member
21 may completely or substantially completely fill conduit 19 and
cavity 18. Conduit 19 may be relatively long or relatively short,
i.e., the lower end part of cavity 18.
Porous element 21 of the preferred abrading block of the invention
is preferably held into conduit 19 by frictional engagement,
filling at least the bottom portion of conduit 19 from side to side
to substantially prevent the free flow of liquid from cavity 18.
Other means of attachment of porous element 21 are also possible
such as adhesive bonding. Frictional engagement is preferred
because it permits repositioning downward (i.e., outward from
surface 12) of porous element 21 as its exposed end 23 wears away
in use.
Because of the present popularity of coated abrasive sheet
materials having a pressure-sensitive adhesive on the back side for
attachment, bottom surface 12 is preferably adapted for attachment
of such sheet materials. For this purpose it may be desirable to
adhere or otherwise fasten to bottom surface 12 a sheet 26 of
plastic material which may be more desirable for attachment of the
pressure-sensitive adhesive coating of the coated abrasive sheet.
Such a sheet of plastic material may be formed of a vinyl plastic
or any other material to which pressure-sensitive adhesive coated
material may adhere and from which it may easily be removed when
the useful life of the abrasive sheet is over or when the abrasive
sheet otherwise requires removal.
The liquid employed as a lubricant in abrading operations in cavity
18 preferably is water but other liquids may also be employed such
as solutions of various salts which impart some improvement in the
abrading operation or mixtures of water and organic liquids or
organic liquids alone, depending upon the particular materials used
and the particular abrading operation carried out.
The preferred abrading block of the present invention has a round
opening 13 in bottom surface 12 which typically varies from about
1/2 inch to 2 inches in diameter. The opening should be of a
sufficient size to permit an adequate amount of porous element 21
to be exposed and contact the surface being finished to provide for
an adequate quantity of liquid on the surface. The most preferred
embodiment has a central opening having a diameter of 11/2
inch.
The preferred embodiment also has a vent hole 20, preferably about
1/4 inch in diameter, to permit air to enter cavity 18, permitting
release of water from cavity 18 under the force of gravity.
The abrasive sheet, of course, may contain more than one opening,
provided a sufficient number of such openings are aligned with the
opening in the bottom surface of the body and provided that the
aligned openings in the abrasive sheet are of sufficient size to
permit the porous element to extend therethrough to provide a
sufficient quantity of liquid on the surface of the surface being
finished.
Other modifications in the abrading pad of the abrading block of
the present invention are contemplated without departing from the
scope of the claims.
* * * * *